package com.zenithmind.version.service.impl;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.zenithmind.common.context.UserContext;
import com.zenithmind.version.mapper.FileVersionMapper;
import com.zenithmind.version.pojo.domain.FileVersion;
import com.zenithmind.version.pojo.dto.FileVersionCreateDTO;
import com.zenithmind.version.pojo.query.FileVersionQueryDTO;
import com.zenithmind.version.pojo.vo.FileVersionVO;
import com.zenithmind.version.service.FileVersionService;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 文件版本服务实现类
 * 
 * @author ZenithMind Team
 * @since 2025-01-09
 */
@Slf4j
@Service
@RequiredArgsConstructor
public class FileVersionServiceImpl extends ServiceImpl<FileVersionMapper, FileVersion> implements FileVersionService {

    @Override
    @Transactional(rollbackFor = Exception.class)
    public FileVersionVO createFileVersion(FileVersionCreateDTO createDTO) {
        log.info("创建文件版本: {}", createDTO.getFilePath());
        
        FileVersion fileVersion = new FileVersion();
        BeanUtils.copyProperties(createDTO, fileVersion);
        
        // 生成版本号
        Integer maxVersion = baseMapper.getMaxVersionNumber(
                createDTO.getRepositoryId(), 
                createDTO.getFilePath(), 
                createDTO.getBranchName()
        );
        fileVersion.setVersionNumber(maxVersion + 1);
        
        fileVersion.setCreateTime(LocalDateTime.now());
        fileVersion.setUpdateTime(LocalDateTime.now());
        
        save(fileVersion);
        
        return convertToVO(fileVersion);
    }

    @Override
    public IPage<FileVersionVO> getFileVersionPage(FileVersionQueryDTO queryDTO) {
        log.info("分页查询文件版本");
        
        Page<FileVersionVO> page = queryDTO.toPage();
        
        return baseMapper.selectFileVersionPageWithDetails(
                page,
                queryDTO.getRepositoryId(),
                queryDTO.getFilePath(),
                queryDTO.getBranchName()
        );
    }

    @Override
    public FileVersionVO getFileVersionDetail(String id) {
        log.info("获取文件版本详情: {}", id);
        
        FileVersion fileVersion = getById(id);
        if (fileVersion == null) {
            throw new RuntimeException("文件版本不存在");
        }
        
        return convertToVO(fileVersion);
    }

    @Override
    public List<FileVersionVO> getFileVersionHistory(String repositoryId, String filePath, String branchName, Integer limit) {
        log.info("获取文件版本历史: repositoryId={}, filePath={}, branchName={}", repositoryId, filePath, branchName);
        
        return baseMapper.selectFileVersionHistory(repositoryId, filePath, branchName, limit);
    }

    @Override
    public FileVersionVO getCurrentFileVersion(String repositoryId, String filePath, String branchName) {
        log.info("获取文件当前版本: repositoryId={}, filePath={}, branchName={}", repositoryId, filePath, branchName);
        
        return baseMapper.selectCurrentFileVersion(repositoryId, filePath, branchName);
    }

    @Override
    public List<FileVersionVO> getCommitFiles(String commitId) {
        log.info("获取提交中的文件列表: commitId={}", commitId);
        
        return baseMapper.selectCommitFiles(commitId);
    }

    @Override
    public List<FileVersionVO> getBranchFiles(String repositoryId, String branchName, String directory) {
        log.info("获取分支中的文件列表: repositoryId={}, branchName={}, directory={}", repositoryId, branchName, directory);
        
        return baseMapper.selectBranchFiles(repositoryId, branchName, directory);
    }

    @Override
    public Object compareFileVersions(String repositoryId, String filePath, String fromVersion, String toVersion) {
        log.info("比较文件版本差异: repositoryId={}, filePath={}, fromVersion={}, toVersion={}", 
                repositoryId, filePath, fromVersion, toVersion);
        
        return baseMapper.compareFileVersions(repositoryId, filePath, fromVersion, toVersion);
    }

    @Override
    public String getFileContent(String versionId) {
        log.info("获取文件内容: versionId={}", versionId);
        
        return baseMapper.selectFileContent(versionId);
    }

    @Override
    public List<FileVersionVO> searchFiles(String repositoryId, String keyword, String branchName, String fileType, Integer limit) {
        log.info("搜索文件: repositoryId={}, keyword={}", repositoryId, keyword);
        
        return baseMapper.searchFiles(repositoryId, keyword, branchName, fileType, limit);
    }

    @Override
    public Object getFileStatistics(String repositoryId, String filePath) {
        log.info("获取文件统计信息: repositoryId={}, filePath={}", repositoryId, filePath);
        
        return baseMapper.selectFileStatistics(repositoryId, filePath);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public FileVersionVO restoreFileVersion(String repositoryId, String filePath, String branchName, String targetVersion, String userId) {
        log.info("恢复文件版本: repositoryId={}, filePath={}, branchName={}, targetVersion={}", 
                repositoryId, filePath, branchName, targetVersion);
        
        String newVersionId = baseMapper.restoreFileVersion(repositoryId, filePath, branchName, targetVersion, userId);
        FileVersion newVersion = getById(newVersionId);
        
        return convertToVO(newVersion);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public FileVersionVO copyFileToBranch(String repositoryId, String filePath, String sourceBranch, String targetBranch, String userId) {
        log.info("复制文件到分支: repositoryId={}, filePath={}, sourceBranch={}, targetBranch={}", 
                repositoryId, filePath, sourceBranch, targetBranch);
        
        String newVersionId = baseMapper.copyFileToBranch(repositoryId, filePath, sourceBranch, targetBranch, userId);
        FileVersion newVersion = getById(newVersionId);
        
        return convertToVO(newVersion);
    }

    @Override
    @Transactional(rollbackFor = Exception.class)
    public Boolean batchDeleteFileVersions(List<String> versionIds) {
        log.info("批量删除文件版本: {}", versionIds);
        
        return baseMapper.batchDeleteFileVersions(versionIds) > 0;
    }

    @Override
    public Object getFileChangeStatistics(String repositoryId, String startTime, String endTime) {
        log.info("获取文件变更统计: repositoryId={}, startTime={}, endTime={}", repositoryId, startTime, endTime);
        
        return baseMapper.selectFileChangeStatistics(repositoryId, startTime, endTime);
    }

    @Override
    public List<Object> getHotFiles(String repositoryId, Integer limit) {
        log.info("获取热门文件: repositoryId={}", repositoryId);
        
        return baseMapper.selectHotFiles(repositoryId, limit);
    }

    @Override
    public Object getFileTree(String repositoryId, String branchName, String path) {
        log.info("获取文件目录树: repositoryId={}, branchName={}, path={}", repositoryId, branchName, path);

        // 参数验证
        if (repositoryId == null || repositoryId.trim().isEmpty()) {
            throw new IllegalArgumentException("仓库ID不能为空");
        }
        if (branchName == null || branchName.trim().isEmpty()) {
            throw new IllegalArgumentException("分支名称不能为空");
        }

        // 这里应该实现Git文件树获取逻辑，暂时返回简单结构
        Map<String, Object> fileTree = new HashMap<>();
        fileTree.put("repositoryId", repositoryId);
        fileTree.put("branchName", branchName);
        fileTree.put("path", path != null ? path : "/");
        fileTree.put("files", new ArrayList<>());
        fileTree.put("directories", new ArrayList<>());

        log.info("获取文件目录树完成: {}/{}", repositoryId, branchName);
        return fileTree;
    }

    @Override
    public byte[] downloadFileVersion(String versionId, String userId) {
        log.info("下载文件版本: versionId={}, userId={}", versionId, userId);

        // 参数验证
        if (versionId == null || versionId.trim().isEmpty()) {
            throw new IllegalArgumentException("版本ID不能为空");
        }

        // 检查文件版本是否存在
        FileVersion fileVersion = getById(versionId);
        if (fileVersion == null) {
            throw new RuntimeException("文件版本不存在: " + versionId);
        }

        // 这里应该实现文件下载逻辑，暂时返回空字节数组
        log.info("文件下载完成: {}", versionId);
        return new byte[0];
    }

    @Override
    public Object previewFile(String versionId, String userId) {
        log.info("获取文件预览: versionId={}, userId={}", versionId, userId);

        // 参数验证
        if (versionId == null || versionId.trim().isEmpty()) {
            throw new IllegalArgumentException("版本ID不能为空");
        }

        // 检查文件版本是否存在
        FileVersion fileVersion = getById(versionId);
        if (fileVersion == null) {
            throw new RuntimeException("文件版本不存在: " + versionId);
        }

        // 构建预览信息
        Map<String, Object> preview = new HashMap<>();
        preview.put("versionId", versionId);
        preview.put("fileName", fileVersion.getFileName());
        preview.put("filePath", fileVersion.getFilePath());
        preview.put("mimeType", fileVersion.getMimeType());
        preview.put("content", "文件预览内容"); // 这里应该读取实际文件内容

        log.info("文件预览获取完成: {}", versionId);
        return preview;
    }

    /**
     * 转换为VO
     */
    private FileVersionVO convertToVO(FileVersion fileVersion) {
        FileVersionVO vo = new FileVersionVO();
        BeanUtils.copyProperties(fileVersion, vo);

        // 补充字段转换
        if (fileVersion.getCreateTime() != null) {
            vo.setCreateTime(fileVersion.getCreateTime());
        }
        if (fileVersion.getUpdateTime() != null) {
            vo.setUpdateTime(fileVersion.getUpdateTime());
        }

        return vo;
    }
}
